Meet Mattias De Zalenski, Software Engineer at Northvolt

What do you do?

Formally, I am in the automation team. But, I’ve also been a developer in the battery systems team – building the BMS system from the ground up. I’ve handled the first battery testing in ABB facilities. I also work with our connectivity and maintenance for our customer Epiroc. Our aim is to see how the batteries behave optimally. We measure simple things like voltage and capacity, but also how it changes over time. Any measure will be important for the battery warranty and extending its lifetime. By detecting different conditions, we can come up with better ways of using energy.

You worked at Spotify before you came here. What was that like?

Working at Spotify was amazing. I joined them quite early, so I saw the tremendous growth that happened. But the vision was always the same – to give music to the world – and it was a great journey to be a part of. At Spotify, I worked a lot on the playlist systems building it from scratch. I did this for several years, and then big backing systems and how to transition into cloud software. The playlist is the project I am most proud of. It was a need very early on – the ability to store music however you like.

I got involved with Spotify because I knew some friends from the Royal Institute of Technology. They’d been involved from the start, and one of them asked me to come along and help out for a couple of days. The rest is history.

How did you find Northvolt?

I’d been at Spotify for a very long time, and I had been studying physics in college. I was interested in energy systems and the future of energy. I had read some pieces on Northvolt in the news, so I went to a tech conference in Stockholm to get familiar with the company.

What was your first impression coming to the office?

It was very interesting to hear about the projects and ambition. My first impression was great. It was a playground in the spring when we started everything. We got to build modules from the ground-up. We’ve written simple programs that push electricity in and out of the batteries, and then measure how they behave. I guess for me, it’s that it’s challenging in many different ways. I get to do physics and electrical, and sometimes I’m even there with a big wrench building stuff.

What was it like working on the Epiroc project?

It was a big first project for us, and it still remains a challenge. The product has to work underground with all kinds of temperatures and harsh surroundings. There is a lot of testing involved, but the advantages of using cells versus diesel are really worthwhile. It is quite rewarding seeing all the parts come together, and we were able to deliver our first packs on time. If we can do this, we can do anything.

Now, we are moving to the factory site and we have a similar vision there. We want to take our devices and get all the data that we can possibly measure, and then track the cells through the process. The goal will always be to improve yield and quality.

What did you study?

I did mathematics in high school and then continued with it when I went to the University of Cambridge. It became two years of math and a year of computer science. I’ve loved playing with computers ever since I was a kid. I’m self-taught in programming, and I remember building computer games with my friends from the age of ten. My interest in computers remained, and I competed in computer programming competitions – many of them international. I took part in organizing a 24-hour contest in Hungary where model cars had to be controlled by the computers. That was a great deal of fun.

You have a long history with music other than Spotify.

Yes, I was a lisp developer at NoteHeads. It was a program to create sheet music for the orchestra. We’d create algorithms for proper sheet music spacing and natural instrument playback. I also play a little bit of piano myself, along with guitar and the clarinet. 

What do you like to do when you are not here?

I love traveling, and sometimes I like to break out a couple of moves on the dance floor.